This invention relates to toothbrushes and in particular toothbrushes for use in oral hygiene systems suited for use by bedridden users.
Conventionally, water is applied to the bristled head of a toothbrush to assist the cleaning action of a dentifrice applied to its bristles, and following brushing, it is usual to rinse the mouth. To the able bodied or to those able to sit upright without undue difficulty, cleaning the teeth is not particularly troublesome.
However, when it is the case of a bedridden patient, not able to sit upright, or only able to sit upright with considerable difficulty and discomfort, cleaning the teeth is particularly troublesome, and especially rinsing the mouth, as neither the application of fluid to assist the action of the dentifrice nor subsequent rinsing of the mouth can be effected in conventional manner with the patient in the prone position.
It is known from such as U.S. Pat. No. 4,672,953 to provide a toothbrush with first and second passageway means through the handle for the supply of fluid to the bristles of the brush and its removal from the patient""s mouth by suction, in an attempt to overcome the difficulties mentioned above in relation to patients who must, of necessity, remain in a prone position.
However, such a construction still leaves room for improvement in the sense that with prone patients it can frequently occur that the patient""s mouth inadvertently closes on to the toothbrush during use causing an undesired build-up of vacuum during removal of spent fluid. This problem is attended to in European Patent Number 0557337B where a toothbrush construction is provided that ensures that in the circumstance when a patient""s mouth does inadvertently close on to the toothbrush there is the substantial guarantee that a vacuum buildup in the mouth is prevented.
The object of the present invention is to provide a toothbrush construction of simpler and less expensive construction but with the same time a significantly improved ability to provide and remove fluid and prevent a vacuum build-up.
According to the present invention, a toothbrush comprises a handle with a head portion at one end, a recess in the head, a bristle pack located in the recess with the bristles attached by one end to the base of the recess, the recess opening being bounded by inwardly directed shoulders, and the outer extremities of the bristles lying in abutting relationship with the inner faces of the shoulders, and there being a fluid supply line provided along or through the handle and communicating with the recess. Preferably, the bristle pack is formed by a number of clusters of bristles, it being the outermost clusters that are in close abutting relationship with the edges of the shoulders of the recess, and adjacent clusters at least at the edges of the pack being in close but spaced relationship.
Thus, and in use, water or cleansing agent cam be supplied to the bristle pack to emerge from the bristle pack during teeth cleaning, and simultaneously, the connection of the vacuum line to a source of reduced pressure or a vacuum pump causes the extraction of water or cleansing fluid from the mouth.
Most desirably, the bristle pack is dimensioned such that it locates in the recess in the bristle head with clearance on all four sides, the outer bristles or bristle clusters extending vertically from the base of the recess in alignment with the edges of the flanges at the edges of the recess to ensure that vacuum is provided around the whole of the bristle pack.
By having the bristles or bristle clusters at the edge of the bristle pack in abutting engagement with the faces of the shoulders at the edges of the recess, there is a major concentration of vacuum created around the base of the bristles between adjacent bristles or bristle clusters not only at the edges of the bristle pack, but also over the whole of its area, maximizing the extraction of fluid from the mouth of the user.
Able bodied users can deal adequately with fluid in the mouth should it be that removal of fluid is not at the same rate as the supply of water or cleansing fluid. However, with users who must remain prone, are ill or semi-conscious, it is essential that control of water or cleansing fluid supply to the mouth is balanced with the rate of extraction, to ensure that the mouth of the user does not fill with fluid.
Equally, it is important that if such users close their mouth around the toothbrush, an excess vacuum does not build up in the mouth. It is therefore desirable that there is an air vent means located on the handle and extending along the handle form a position in close proximity to the bristles, the air vent means having an inlet to longitudinal spaced relationship along the length of the handle to prevent the inlet being closed by the lips of the user.
The vent may be a tube-like member located on the handle, but preferably the vent is formed by at least one and preferably two diametrically opposed passageways within the confines of the handle, with longitudinally spaced access holes through the outer wall of the passageway.
To enable the toothbrush of the invention to be used in conjunction with a machine such as is disclosed in European Patent Number 0557337B, the end of the handle remote form the bristle head may be fashioned as a plug-like connector, the machine being provided with a mating plug-like connector such that the first chamber can be connected to a source of vacuum, i.e., to a fluid pump on the machine, by one simple act. It enables a brush to be dedicated to a particular use in the circumstances where it is the machine of European Patent Number 0557337B, and in use as in such as a hospital.